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False positive FES warning for loadModel(path, callback)

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#9,295 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
62/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
javascript
Domain
developer-experience

Research direction

The warning comes from the Friendly Error System's argument checks for loadModel(), so start there and find the branch that expects a string as the second parameter. Compare it with the fix in PR #9286, which handled loadModel(path, true), and make the callback form pass the same check. Done when loadModel(path, callback) with a valid callback logs no FES warning, and loadModel(path, true) still behaves as before.

Written by the indexing model from the issue text.

Description

p5.js 2.0+
Most appropriate sub-area of p5.js?
  • Accessibility
  • Color
  • Core/Environment/Rendering
  • Data
  • DOM
  • Events
  • Image
  • IO
  • Math
  • Typography
  • Utilities
  • WebGL
  • WebGPU
  • p5.strands
  • Build process
  • Unit testing
  • Internationalization
  • Friendly errors
  • Other (specify if possible)
p5.js version

2.3.4

Web browser and version

Google Chrome 155.0.8059.40 (Official Build) (64-bit)

Operating system

Windows 11 Version 25H2 (Build 26200.9457)

Steps to reproduce this
Steps:
  1. Open the p5.js Web Editor.
  2. Upload a valid teapot.obj file into an assets folder in the sketch.
  3. Run the following sketch and check the console.
Snippet:
let teapot;

function setup() {
  createCanvas(400, 400, WEBGL);

  loadModel("/assets/teapot.obj", function (modelData) {
    teapot = modelData;
    console.log("Model loaded successfully:", modelData);
  });
}

function draw() {
  background(220);
  orbitControl();
  normalMaterial();

  if (teapot) {
    scale(2);
    model(teapot);
  }
}
Expected behavior

Calling loadModel(path, callback) with a valid callback should not produce a Friendly Error System (FES) warning.

Actual behavior

The model loads and renders successfully, and the callback executes. However, FES reports:

p5.js says: Expected string at the second parameter in loadModel().

This appears to be a false positive because the callback is a valid second argument for this overload.

Additional context

This is a follow-up to Issue #9176 and it's fix PR #9286 , which addressed the false-positive FES warning for loadModel(path, true).

The callback overload loadModel(path, callback) still produces a similar warning after that fix. I reproduced this behavior in the p5.js Web Editor using a local OBJ file.

I'd like to work on this issue if approved. Could a maintainer please review it and assign it to me if appropriate?

Screenshot of Issue Visually
Image
Dominant language
JavaScript
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Forks
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Avg merge
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Merged PRs (30d)
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